How does the pre-launch condensation vapor differ from the exhaust plume generated during launch?

Answer

The pre-launch vapor is passive and vanishes easily, while the exhaust is a sustained, energetic reaction product

The pre-launch vapor is a cold-weather phenomenon that vanishes quickly, whereas the launch exhaust is the product of controlled chemical reaction and immense thermal energy, appearing as a sustained, energetic event.

How does the pre-launch condensation vapor differ from the exhaust plume generated during launch?
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